This might actually be on @github side, but post here for your comments.
I'm finding that sometimes the jekyll source files on github appear on search engines above the actual rendered files. Github surely has better SEO, but it leads to undesired references.
The only solution I find is to close the repo so that the source files are not indexed.
Would it be a better solution if @github includes a canonical rel to all source files within the gh-pages branch?
Good question! You should include a canonical rel in the <head> of your layout. It would not be in the best interest of this project to auto-inject canonical URLs to rendered gh-pages sites.
GitHub Pages uses Jekyll, but the membership of the team that works on GH Pages is, I have been told, transient. I'd write GH Support if you want to talk to a GH Pages rep.
Thank @parkr! I´ll contact @github but it´s going to be tricky. I´m not sure adding a canonical rel on my rendered pages would attract the source files pages on github.com since they are different domains.
Thanks for the reply though.